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The fish community as an indicator of water quality in the marsh of Kovilj [Serbia, Yugoslavia]
2001
Maletin, S. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Miljanovic, B. | Djukic, N. | Sipos, S.
In order to carry out the program of protection and rational exploitation of Kovilj Marsh (Serbia, Yugoslavia), which is a part of special natural reserve called the Marsh of Kovilj and Petrovaradin, we have done an ecological analysis of the fish community. The research was conducted during the period of "low water", in the autumn 2000, on the following locations: Slajz, Tonja and Arkanj, and we have established the presence of 12 species from 6 different families. The saprobic index of the majority of bioindicative species shows that the water belongs to the beta-mesosaprobic type (the saprobic index according to Pantle-Buck is 2.1). The presence and abundance of certain ecological groups of fish is examined in relation to migration, type of food and type of substrate on which the fish lay their eggs. The results of this examination point to main features of certain localities in this floodplain, as well as to the necessity of taking appropriate measures of protection of this valuable water resource.
显示更多 [+] 显示较少 [-]Oiling of the continental shelf and coastal marshes over eight years after the 2010 Deepwater Horizon oil spill 全文
2019
Turner, R Eugene | Rabalais, Nancy N. | Overton, Edward B. | Meyer, Buffy M. | McClenachan, Giovanna | Swenson, Erick M. | Besonen, Mark | Parsons, Michael L. | Zingre, Jeffrey
We measured the temporal and spatial trajectory of oiling from the April, 2010, Deepwater Horizon oil spill in water from Louisiana's continental shelf, the estuarine waters of Barataria Bay, and in coastal marsh sediments. The concentrations of 28 target alkanes and 43 target polycyclic aromatic hydrocarbons were determined in water samples collected on 10 offshore cruises, in 19 water samples collected monthly one km offshore at 13 inshore stations in 2010 and 2013, and in 16–60 surficial marsh sediment samples collected on each of 26 trips. The concentration of total aromatics in offshore waters peaked in late summer, 2010, at 100 times above the May, 2010 values, which were already slightly contaminated. There were no differences in surface or bottom water samples. The concentration of total aromatics declined at a rate of 73% y−1 to 1/1000th of the May 2010 values by summer 2016. The concentrations inside the estuary were proportional to those one km offshore, but were 10–30% lower. The oil concentrations in sediments were initially different at 1 and 10 m distance into the marsh, but became equal after 2 years. Thus, the distinction between oiled and unoiled sites became blurred, if not non-existent then, and oiling had spread over an area wider than was visible initially. The concentrations of oil in sediments were 100–1000 times above the May 2010 values, and dropped to 10 times higher after 8 years, thereafter, demonstrating a long-term contamination by oil or oil residues that will remain for decades. The chemical signature of the oil residues offshore compared to in the marsh reflects the more aerobic offshore conditions and water-soluble tendencies of the dissolved components, whereas the anaerobic marsh sediments will retain the heavier molecular components for a long time, and have a consequential effect on the ecosystems.
显示更多 [+] 显示较少 [-]Composition and depth distribution of hydrocarbons in Barataria Bay marsh sediments after the Deepwater Horizon oil spill 全文
2016
Dincer Kırman, Zeynep | Sericano, José L. | Wade, Terry L. | Bianchi, Thomas S. | Marcantonio, Franco | Kolker, Alexander S.
In 2010, an estimate 4.1 million barrels of oil were accidentally released into the Gulf of Mexico (GoM) during the Deepwater Horizon (DWH) Oil Spill. One and a half years after this incident, a set of subtidal and intertidal marsh sediment cores were collected from five stations in Barataria Bay, Louisiana, USA, and analyzed to determine the spatial and vertical distributions and source of hydrocarbon residues based on their chemical composition. An archived core, collected before the DWH oil spill from the same area, was also analyzed to assess the pre-spill hydrocarbon distribution in the area. Analyses of aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs) and stable carbon isotope showed that the distribution of petroleum hydrocarbons in Barataria Bay was patchy and limited in areal extent. Significant TPH and ΣPAH concentrations (77,399 μg/g and 219,065 ng/g, respectively) were detected in the surface sediments of one core (i.e., core A) to a depth of 9 cm. Based on a sedimentation rate of 0.39 cm yr−1, determined using 137Cs, the presence of anthropogenic hydrocarbons in these sediment core deposited ca. 50 to 60 years ago. The historical background hydrocarbon concentrations increased significantly at the sediment surface and can be attributed to recent inputs. Although the oil present in the bay's sediments has undergone moderate weathering, biomarker analyses performed on core A samples likely indicated the presence of hydrocarbons from the DWH oil spill. The effects of oiling events on Barataria Bay and other marsh ecosystems in this region remain uncertain, as oil undergoes weathering changes over time.
显示更多 [+] 显示较少 [-]Influence of environmental factors on the response of a natural population of Daphnia magna (Crustacea: Cladocera) to spinosad and Bacillus thuringiensis israelensis in Mediterranean coastal wetlands 全文
2010
Duchet, C. | Caquet, Th | Franquet, E. | Lagneau, C. | Lagadic, L.
Influence of environmental factors on the response of a natural population of Daphnia magna (Crustacea: Cladocera) to spinosad and Bacillus thuringiensis israelensis in Mediterranean coastal wetlands 全文
2010
Duchet, C. | Caquet, Th | Franquet, E. | Lagneau, C. | Lagadic, L.
The present study was undertaken to assess the impact of a candidate mosquito larvicide, spinosad (8, 17 and 33 μg L−1) on a field population of Daphnia magna under natural variations of water temperature and salinity, using Bti (0.16 and 0.50 μL L-1) as the reference larvicide. Microcosms (125 L) were placed in a shallow temporary marsh where D. magna was naturally present. The peak of salinity observed during the 21-day observation period may have been partly responsible for the decrease of daphnid population density in all the microcosms. It is also probably responsible for the absence of recovery in the microcosms treated with spinosad which caused a sharp decrease of D. magna abundance within the first two days following treatment whereas Bti had no effect. These results suggest that it may be difficult for a field population of daphnids to cope simultaneously with natural (water salinity and temperature) and anthropogenic (larvicides) stressors.
显示更多 [+] 显示较少 [-]Influence of environmental factors on the response of a natural population of Daphnia magna (Crustacea: Cladocera) to spinosad and Bacillus thuringiensis israelensis in Mediterranean coastal wetlands 全文
2010
Duchet, Claire | Caquet, Thierry | Franquet, Evelyne | Lagneau, C. | Lagadic, Laurent | Écologie et santé des écosystèmes (ESE) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | Entente Interdépartementale pour la Démoustication du Littoral Méditerranéen | Institut Méditerranéen d'Ecologie et de Paléoécologie (IMEP) ; Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Avignon Université (AU)-Centre National de la Recherche Scientifique (CNRS)
The present study was undertaken to assess the impact of a candidate mosquito larvicide, spinosad (8, 17 and 33 μg L−1) on a field population of Daphnia magna under natural variations of water temperature and salinity, using Bti (0.16 and 0.50 μL L−1) as the reference larvicide. Microcosms (125 L) were placed in a shallow temporary marsh where D. magna was naturally present. The peak of salinity observed during the 21-day observation period may have been partly responsible for the decrease of daphnid population density in all the microcosms. It is also probably responsible for the absence of recovery in the microcosms treated with spinosad which caused a sharp decrease of D. magna abundance within the first two days following treatment whereas Bti had no effect. These results suggest that it may be difficult for a field population of daphnids to cope simultaneously with natural (water salinity and temperature) and anthropogenic (larvicides) stressors. Significant interaction between salinity and spinosad exposure impairs the recovery of a natural population of Daphnia magna
显示更多 [+] 显示较少 [-]Free atmospheric phosphine concentrations and fluxes in different wetland ecosystems, China 全文
2011
Han, Chao | Geng, Jinju | Hong, Yuning | Zhang, Rui | Gu, Xueyuan | Wang, Xiaorong | Gao, Shixiang | Glindemann, Dietmar
Atmospheric phosphine (PH₃) fluxes from typical types of wetlands and PH₃ concentrations in adjacent atmospheric air were measured. The seasonal distribution of PH₃ in marsh and paddy fields were observed. Positive PH₃ fluxes are significantly related to high air temperature (summer season) and increased vegetation. It is concluded that vegetation speeds up the liberation of PH₃ from soils, while water coverage might function as a diffusion barrier from soils or sediments to the atmosphere. The concentrations of atmospheric PH₃ (ngm⁻³) above different wetlands decrease in the order of paddy fields (51.8±3.1)>marsh (46.5±20.5)>lake (37.0±22.7)>coastal wetland (1.71±0.73). Highest atmospheric PH₃ levels in marsh are found in summer. In paddy fields, atmospheric PH₃ concentrations in flourishing stages are higher than those in slowly growing stages.
显示更多 [+] 显示较少 [-]Assessing the risk of marine litter accumulation in estuarine habitats 全文
2019
Mazarrasa, Inés | Puente, Araceli | Núñez, Paula | García, Andrés | Abascal, Ana J. | Juanes, J. A. (José A.)
Rivers and estuaries are among the main entrances of litter to the marine environment. This study characterizes marine litter deposits in three estuaries of the Gulf of Biscay, assesses its potential impact in estuarine habitats based on expert elucidation, and develops a methodology to estimate the associated environmental risk. Litter was ubiquitous in the estuaries of study, mostly represented by plastic debris and sanitary waste. High marsh communities acted as litter traps, showing significantly higher litter densities than adjacent habitats. The expected impact was valued to be low but different across habitats and possible litter-habitat interactions. The estimated risk was low but different across habitats and estuaries, determined by the probability of encounter and the expected impact. This study contributes to increase the scarce knowledge available on the threat that marine litter poses in estuarine environments and presents a methodology to help identify those habitats under a higher risk.
显示更多 [+] 显示较少 [-]Comparison of phytoremediation potential capacity of Spartina densiflora and Sarcocornia perennis for metal polluted soils 全文
2017
Idaszkin, Yanina L. | Lancelotti, Julio L. | Pollicelli, María P. | Marcovecchio, Jorge E. | Bouza, Pablo J.
Phytoremediation is considered the most appropriate technique to restore metal polluted soil, given its low cost, high efficiency and low environmental impact. Spartina densiflora and Sarcocornia perennis are perennial halophytes growing under similar environmental conditions in San Antonio marsh (Patagonia Argentina), therefore it is interesting to compare their phytoremediation potential capacity. To this end, we compared concentrations of Pb, Zn, Cu, and Fe in soils and in below- and above-ground structures of S. perennis and S. densiflora. It was concluded that both species are able to inhabit Pb, Zn, and Cu polluted soils. Although Sarcocornia translocated more metals to the aerial structures than Spartina, both species translocated only when they were growing in soils with low metal concentrations. It seems that the plants translocate only a certain proportion of the metal contained in the soil. These results suggest that both species could be considered candidates to phytostabilize these metals in polluted soils.
显示更多 [+] 显示较少 [-]Assessment of factors enabling halite formation in a marsh in a humid temperate climate (Ajó Marsh, Argentina) 全文
2016
Carol, Eleonora S. | Álvarez, María del Pilar | Borzi, Guido E.
The formation of evaporites associated with the final stages of the precipitation sequence, such as the case of halite, is frequent in marshes in arid areas, but it is not to be expected in those humid climates. This work, by means of the study of the hydrological, climatic and land use conditions, identifies the factors that allow the formation of saline precipitations in a marsh located in a humid climate area. The results obtained show that the exclusion of the marsh as a result of the embankment is the main reason for the presence of halite. It is to be expected that in the future the growth of the embanked marsh areas, together with the climatic and tidal condition tendencies recorded, will favour a higher rate of formation of evaporite salts. The identification of these factors makes it possible to set basic sustainable management guidelines to avoid soil salinisation.
显示更多 [+] 显示较少 [-]Effects of sediment amended with Deepwater Horizon incident slick oil on the infaunal amphipod Leptocheirus plumulosus 全文
2016
Lotufo, Guilherme R. | Farrar, J Daniel | Biedenbach, James M. | Laird, Jennifer G. | Krasnec, Michelle O. | Lay, Claire | Morris, Jeffrey M. | Gielazyn, Michel L.
Crude oil released from the Deepwater Horizon disaster into the Gulf of Mexico posed potential impacts to infaunal invertebrates inhabiting near shore habitats. The effects of sediment-associated weathered slick oil on the amphipod Leptocheirus plumulosus was assessed using 28-d exposures to total PAH sediment concentrations ranging from 0.3 to 24mg/kg (sum of 50 PAHs or tPAH50). Survival and growth rate were significantly decreased in the 2.6, 11.4 and 24.2mg/kg treatments, but only growth in 5.5mg/kg. Offspring production was dramatically decreased but was variable and significantly different only for 24.2mg/kg. The concentrations associated with 20% decreases relative to reference were 1.05 (95% CI=0–2.89) mg/kg tPAH50 for growth rate and 0.632 (95% CI=0.11–2.15) mg/kg tPAH50 for offspring production. The concentrations of PAHs affecting amphipods are within the range of concentrations measured in marsh areas reportedly impacted by DWH oil after its release.
显示更多 [+] 显示较少 [-]The amount and accumulation rate of plastic debris on marshes and beaches on the Georgia coast 全文
2015
Lee, Richard F. | Sanders, Dorothea P.
The amount and accumulation rate of plastic debris at 20 sites along the Georgia coast were prepared using data reported by a number of volunteer organizations. The amount of plastic debris at highly visited barrier island beaches and estuarine marshes ranged from 300 to >1000kg. Relatively large amount of plastics (180–500kg) were found on less visited barrier island beaches, i.e. Blackbeard, Ossabaw and Cumberland Islands. A follow up monthly or quarterly collection study was carried out on two of the sites, a barrier beach and estuarine marsh, to determine accumulation rate in 8000m2 areas. Accumulation rates ranged from 0.18 to 1.28kg/30days–8000m2 on the barrier island beach and from 0.6 to 1.61kg/30days–8000m2 at the estuarine marsh site. The major type of plastics, e.g. bottles, food wrappers, plastic fragments, was highly variable at different seasons and sites. The authors recommend consideration of a standardization in reporting plastic debris, with respect to quantitation of debris and sample area.
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